Abstract

Recent experimental progress with Alkaline-Earth atoms has opened the door to quantum
computing schemes in which qubits are encoded in long-lived nuclear spin states, and the
metastable electronic states of these species are used for manipulation and readout of the
qubits. Here we discuss a variant of these schemes, in which gate operations are performed
in nuclear-spin-dependent optical lattices, formed by near-resonant
coupling to the metastable excited state. This provides an alternative to a previous
scheme [Phys. Rev. Lett. 101, 170504 (2008)], which involved independent
lattices for different electronic states. As in the previous case, we
show how existing ideas for quantum computing with Alkali atoms such as entanglement via
controlled collisions can be freed from important technical restrictions. We also provide
additional details on the use of collisional losses from metastable states to perform gate
operations via a lossy blockade mechanism.